class Student {
	private int no;
	private String name;
	private int age;

	Student(int no, String name, int age) {
		this.no = no;
		this.name = name;
		this.age = age;	
	}

	public void setAge(int age) {
		this.age = age;
	}

	public int getAge() {
		return age;
	}
	public static void main(String[] args) {
		Student students[] = {
			new Student(1, "Zhang3", 19),
			new Student(2, "Li4", 20),
			new Student(3, "Wang5", 21),
		};
		for (int i = 0; i < students.length; i++) {
			students[i].setAge(students[i].getAge()+1);
		}

		for (int i = 0; i < students.length; i++) {
			System.out.println(students[i].getAge());
		}

		System.out.println("---------------------------------------");
		
		for (int i = 0; i < students.length; i++) {
			if (students[i].getAge() > 20)
				System.out.println(students[i].getAge());
		}
		
	}
}
